There are widespread concerns that near-elderly Americans (55-64 years old) face increasing barriers to obtaining health care during a time of significant life transitions and deteriorating health. The long-term objective of the proposed research is to examine determinants of access to care, use of services, and health-related outcomes in the near-elderly. The specific aims are to determine the role of 1) significant recent life transitions such as changes in health insurance, health, work, or income, 2) financial and non-financial incentives in a person's current health insurance plan, 3) the healthcare environment (e.g., managed care market share, rural/urban), and 4) family history (e.g., parental health and early life experiences). Disparities in access to care are examined for women and persons with low income or poor health, as these vulnerable subgroups may have additional difficulties overcoming barriers to care. This study builds on the strengths of the Wisconsin Longitudinal Study (WLS). For 44 years, the WLS has followed men and women who graduated from Wisconsin high schools in 1957 (N=10,317) and a randomly selected sibling (N=7,638). Data were collected on mental and physical health, health insurance, socioeconomic status, and occupational histories. WLS project leaders have proposed a new round of telephone and mail surveys in 2002-03 of the surviving graduates and their siblings. This proposal extends the WLS by 1) adding items on health insurance, access to care, use of health services, and health outcomes to the WLS telephone and mail surveys, 2) collecting detailed information on health plan characteristics through a survey of health insurance companies, 3) linking to environmental data from the Area Resource File and Interstudy, and 4) linking eligible sibling records to Medicare enrollment and claims data. Multilevel modeling will be used to separate the effects of individuals, their health plans, there healthcare environment, and their family history in explaining variation in access to care, use of services, and health outcomes. The proposed research will provide valuable information to policymakers and researchers interested in the health and healthcare experiences of the near-elderly.